In the German patent application No. 41 03 365.5 a pressure control valve being controllable by an electromagnet is described whose tappet-shaped valve-closing member controls the passage between a first pressure agent connection and a second pressure agent connection in the range of a funnel-shaped valve seat surface depending on the stroke. For safeguarding, a pressure-balanced valve actuation and a pressure balancing duct connect the magnet armature chamber (being shielded) by means of a packing seal.
The prior-art valve design generates much noise during the impulse like valve switching phases. This noise is primarily caused by the valve-closing member striking against the valve seat and by the nonsteady flow attitude and, thus, the discontinuous flow around the valve-closing member on account of the binary valve switching positions.
It is, therefore, the object of the invention to improve a pressure control valve of the prior art so that the noise problems are overcome while simultaneously guaranteeing reliable operation and a comparatively simple-design structure.
In accordance with the present invention, the pressure agent transition ducts (to be shut off or to be opened up directly one after the other by the valve-closing member) are positioned between the first and the second pressure agent connections. The pressure agent transition ducts have a cross-sectional area of the valve opening which is variable by steps.